Revisiting the obturator nerve anatomy with a nerve blocking perspective

Yıl 2023, Cilt: 17 Sayı: 1, 22 - 33, 30.04.2023

Turan Koç Orhan Berger Şebnem Rumeli Alev Bobuş Örs Nail Can Öztürk

Öz

Objectives: Accurate nerve block is important for the success of local anesthesia-assisted surgery. Failure to consider the anatomical variations of the targeted nerve anatomy can lead to failure of anesthetic interventions. Given the distinct nature of the obturator nerve, blocking the nerve during clinical procedures is one such problematic situation. The aim of this article is to revisit the anatomy of the obturator nerve in adult cadavers and fetuses in order to discuss in detail its relationship with the obturator nerve block from an anatomical perspective.
Methods: Obturator nerve and its branches were exposed at the posterior wall of the abdomen, lateral wall of the lesser pelvis and anterior aspect of the thigh region in 47 fetuses and 10 adult cadavers. Then, various anatomical variations and morphometry of the obturator nerve were evaluated and measured in detail.
Results: In adult cadavers, the anterior and posterior branches branched 40% in the obturator canal and 60% in the extra-pelvic region, with no branching in the pelvis. In fetuses, the obturator nerve divided into its main branches 8.5% in the pelvis, 33% in the canal and 58.5% distal to the canal. Regarding the muscular branching of the obturator nerve, all adult cadavers showed three fully traceable branches from the anterior and a single branch from the posterior branch.
Conclusion: Our findings regarding the variable branching pattern of the obturator nerve anatomy from the nerve block perspective may help anesthesiologists to improve the success of obturator nerve block by incorporating results from the current and limited number of anatomical data sets.

Anahtar Kelimeler

fetal anatomy, obturator nerve, regional anesthetic techniques

Kaynakça

• Standring S. Gray’s anatomy: the anatomical basis of clinical practice. 40th ed. Edinburgh (Scotland): Elsevier Churchill Livingstone; 2008. p. 1551.
• Bergman RA, Afifi AK, Miyauchi R. Illustrated encyclopedia of human anatomic variation. Opus III: Nervous system: Plexuses [Internet]. [Retrieved on October 11, 2022]. Available from: https://www.anatomyatlases.org/AnatomicVariants/NervousSystem/Text/ObturatorNerve.shtml
• Anagnostopoulou S, Kostopanagiotou G, Paraskeuopoulus T, Chantzi C, Lolis E, Saranteas T. Anatomic variations of the obturator nerve in the inguinal region: implications in conventional and ultrasound regional anesthesia techniques. Reg Anesth Pain Med 2009;34:33–9.
• Tshabalala ZN. The anatomy and clinical implications of the obturator nerve and its branches (Dissertation submitted in full fulfilment of the requirements for the degree Master of Science in Anatomy, University of Pretoria) 2015. [Internet]. [Retrieved on October 11, 2022]. Available from: https://repository.up.ac.za/bitstream/handle/2263/53048/Tshabalala_Anatomy_2015.pdf?sequence=1&isAllowed=y
• Kumka M. Critical sites of entrapment of the posterior division of the obturator nerve: anatomical considerations. J Can Chiropr Assoc 2010;54:33–42.
• Thallaj A, Rabah D. Efficacy of ultrasound-guided obturator nerve block in transurethral surgery. Saudi J Anaesth 2011;5:42–4.
• Moningi S, Durga P, Ramachandran G, Murthy PV, Chilumala RR. Comparison of inguinal versus classic approach for obturator nerve block in patients undergoing transurethral resection of bladder tumors under spinal anesthesia. J Anaesthesiol Clin Pharmacol 2014; 30:41–5.
• Aghamohammadi D, Gargari RM, Fakhari S, Bilehjani E, Poorsadegh S. Classic versus inguinal approach for obturator nerve block in transurethral resection of bladder cancer under spinal anesthesia: a randomized controlled trial. Iran J Med Sci 2018;43:75–80.
• Jo YY, Choi E, Kil HK. Comparison of the success rate of inguinal approach with classical pubic approach for obturator nerve block in patients undergoing TURB. Korean J Anesthesiol 2011;61:143–7.
• Enneking FK, Chan V, Greger J, Hadzić A, Lang SA, Horlocker TT. Lower-extremity peripheral nerve blockade: essentials of our current understanding. Reg Anesth Pain Med 2005;30:4–35.
• McNamee DA, Parks L, Milligan KR. Post-operative analgesia following total knee replacement: an evaluation of the addition of an obturator nerve block to combined femoral and sciatic nerve block. Acta Anaesthesiol Scand 2002;46:95–9.
• Marhofer P, Nasel C, Sitzwohl C, Kapral S. Magnetic resonance imaging of the distribution of local anesthetic during the three-in-one block. Anesth Analg 2000;90:119–24.
• Labat G. Regional anesthesia: its technic and clinical application. 1st ed. Philadelphia (PA): WB Saunders; 1923. p. 496.
• Macalou D, Trueck S, Meuret P, Heck M, Vial F, Ouologuem S, Capdevila X, Virion JM, Bouaziz H. Postoperative analgesia after total knee replacement: the effect of an obturator nerve block added to the femoral 3-in-1 nerve block. Anesth Analg 2004;99:251–4.
• Winnie AP, Ramamurthy S, Durrani Z. The inguinal paravascular technic of lumbar plexus anaesthesia: the “3-in-1” block. Anesth Analg 1973;52:989–96.
• Yoshida T, Nakamoto T, Kamibayashi T. Ultrasound-guided obturator nerve block: a focused review on anatomy and updated techniques. BioMed Res Int 2017;2017:7023750.
• Wassef MR. Interadductor approach to obturator nerve blockade for spastic conditions of adductor thigh muscles. Reg Anesth 1993;18: 13–7.
• Choquet O, Capdevila X, Bennourine K, Feugeas JL, Bringuier-Branchereau S, Manelli JC. A new inguinal approach for the obturator nerve block: anatomical and randomized clinical studies. Anesthesiology 2005;103:1238–45.
• Han C, Ma T, Lei D, Xie S, Ge Z. Effect of ultrasound-guided proximal and distal approach for obturator nerve block in transurethral resection of bladder cancer under spinal anesthesia. Cancer Manag Res 2019;11:2499–505.
• Taha AM. Brief reports: ultrasound-guided obturator nerve block: a proximal interfascial technique. Anesth Analg 2012;114:236–9.
• Horwitz MT. The anatomy of (A) the lumbosacral nerve plexus-its relation to variations of vertebral segmentation, and (B) the posterior sacral nerve plexus. Anat Rec 1939;74:91–107.
• Arora D, Kaushal S, Singh G. Variations of lumbar plexus in 30 adult human cadavers – a unilateral prefixed plexus. The International Journal of Plant, Animal and Environmental Sciences 2014;4:225–8.
• Anloague PA, Huijbregts P. Anatomical variations of the lumbar plexus: a descriptive anatomy study with proposed clinical implications. J Man Manip Ther 2009;17:e107–4.
• Yoshida T, Onishi T, Furutani K, Baba H. A new ultrasound-guided pubic approach for proximal obturator nerve block: clinical study and cadaver evaluation. Anaesthesia 2016;71:291–7.
• Rashiq S, Vandermeer B, Abou-setta AM, Beaupre LA, Jones CA, Dryden DM. Efficacy of supplemental peripheral nerve blockade for hip fracture surgery: multiple treatment comparison. Can J Anesth 2013;60:230–43.
• Akkaya T, Ozturk E, Comert A, Ates Y, Gumus H, Ozturk H, Tekdemir I, Elhan A. Ultrasound-guided obturator nerve block: a sonoanatomic study of a new methodologic approach. Anesth Analg 2009;108:1037–41.
• Katritsis E, Anagnostopoulou S, Papadopoulos N. Anatomical observation on the accessory obturator nerve (based on 1000 specimens). Anat Anz 1980;148:440–5.
• Akkaya T, Comert A, Kendir S, Acar HI, Gumus H, Tekdemir I, Elhan A. Detailed anatomy of accessory obturator nerve blockade. Minerva Anestesiol 2008;74:119–22.
• Atanassoff PG, Weiss BM, Brull SJ, Horst A, Külling D, Stein R, Theiler I. Electromyographic comparison of obturator nerve block to three-in-one block. Anesth Analg 1995;81:529–33.
• Wallace JB, Andrade JA, Christensen JP, Osborne LA, Pellegrini JE. Comparison of fascia iliaca compartment block and 3-in-1 block in adults undergoing knee arthroscopy and meniscal repair. AANA J 2012;80:S37–44.
• Capdevila X, Biboulet PH, Bouregba M, Barthelet Y, Rubenovitch J, d’Athis F. Comparison of the three-in-one and fascia iliaca compartment blocks in adults: clinical and radiographic analysis. Anesth Analg 1998;86:1039–44.